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    <title>Document</title>
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    <script>
        /*
         当访问对象属性的时候，先从自身找，才进入原型里面去找.原型找不到去原型的原型里面找，直到Object.prototype为止
         */
       function Fn() {
        //    this.x = 10;
       }
    //    Fn.prototype.x = 555;
        Object.prototype.x = 666;
       var obj1 = new Fn();
       console.log(obj1.x);

       console.log(Fn.prototype.__proto__ === Object.prototype);

       console.log(Object.prototype);
    </script>
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